/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package org.dom4j.io;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.ElementHandler;
import org.dom4j.ElementPath;

/**
 * This {@link org.dom4j.ElementHandler}is used to trigger {@link
 * ElementModifier} objects in order to modify (parts of) the Document on the
 * fly.
 * 
 * <p> When an element is completely parsed, a copy is handed to the associated
 * (if any) {@link ElementModifier}that on his turn returns the modified
 * element that has to come in the tree. </p>
 * 
 * @author Wonne Keysers (Realsoftware.be)
 */
class SAXModifyElementHandler implements ElementHandler
{
   private ElementModifier elemModifier;

   private Element modifiedElement;

   public SAXModifyElementHandler(ElementModifier elemModifier)
   {
      this.elemModifier = elemModifier;
   }

   public void onStart(ElementPath elementPath)
   {
      this.modifiedElement = elementPath.getCurrent();
   }

   public void onEnd(ElementPath elementPath)
   {
      try
      {
         Element origElement = elementPath.getCurrent();
         Element currentParent = origElement.getParent();

         if(currentParent != null)
         {
            // Clone sets parent + document to null
            Element clonedElem = (Element) origElement.clone();

            // Ask for modified element
            modifiedElement = elemModifier.modifyElement(clonedElem);

            if(modifiedElement != null)
            {
               // Restore parent + document
               modifiedElement.setParent(origElement.getParent());
               modifiedElement.setDocument(origElement.getDocument());

               // Replace old with new element in parent
               int contentIndex = currentParent.indexOf(origElement);
               currentParent.content().set(contentIndex, modifiedElement);
            }

            // Remove the old element
            origElement.detach();
         }
         else
         {
            if(origElement.isRootElement())
            {
               // Clone sets parent + document to null
               Element clonedElem = (Element) origElement.clone();

               // Ask for modified element
               modifiedElement = elemModifier.modifyElement(clonedElem);

               if(modifiedElement != null)
               {
                  // Restore parent + document
                  modifiedElement.setDocument(origElement.getDocument());

                  // Replace old with new element in parent
                  Document doc = origElement.getDocument();
                  doc.setRootElement(modifiedElement);
               }

               // Remove the old element
               origElement.detach();
            }
         }

         // Put the new element on the ElementStack, it might get pruned by
         // the PruningDispatchHandler
         if(elementPath instanceof ElementStack)
         {
            ElementStack elementStack = ((ElementStack) elementPath);
            elementStack.popElement();
            elementStack.pushElement(modifiedElement);
         }
      }
      catch(Exception ex)
      {
         throw new SAXModifyException(ex);
      }
   }

   /**
    * DOCUMENT ME!
    * 
    * @return Returns the modified Element.
    */
   protected Element getModifiedElement()
   {
      return modifiedElement;
   }
}

/*
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided that the
 * following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and
 * notices. Redistributions must also contain a copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived
 * from this Software without prior written permission of MetaStuff, Ltd. For
 * written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may
 * "DOM4J" appear in their names without prior written permission of MetaStuff,
 * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
